like the title says. i started the 383 today for the first time and i have to keep my foot on the gas to crank and keep it running. with my foot on the gas it will usually start right up but it runs a bit erratic. i checked for spark and the plug wire order and theyre fine. im hearing a loud tapping so im guessing at this time i need to readjust my valves but i had noone to keep my car running for me to do so. i would figure the car would still idle with the rockers a little loose but this is my first experience with the comp r's so i dont know.

i havent checked for fuel pressure yet but i have a new walbro pump and an adj. fpr that hasent been tampered with during the rebuild. so i think im good on that

the car is throwing only one code which is code 34 meaining there is something wrong with my map sensor. could this be the cause of my problem?

ive also deleted the egr, air by a madz28 tune

thanks in advance.

 

if your getting a map code, its due to a vaccum problem. If you have an aftermarket TB, try cranking the TB blades open, to adjust for the idle. Also, do you have any sort of scan software?

 

no i dont have any sort of scan equip and a stock tb. ill check around the manifold and tb for any leaks but i have open headers right now so its hard to hear.

 

yes, just spray some carb cleaner around the manifold, and tb areas, and see if the idle rises. Also, are you sure you adjusted the rockers correctly? If they are to tight, it can cause the motor to stumble and fall on its face. But since you are getting the MAP code, it tells me you are losing vaccum..

 

ive been able to get it to run on its own twice so far and it would idle around 1000-1200 rpm's ive done nothing different for it to run on its own but it did. i'll try your suggestion and also readjust my rockers.i feel more comfortable adjusting them with the engine running but its near impossible to hear if theyre adjusted right seeing as my car is pretty loud right now.

 

ive readjusted my rockers and it stays running on its own now but its idleing around 1300rpm. ive sprayed carb cleaner all around the throttle body and intake and everything seems to be sealed up fine. could a faulty map sensor cause this high idle?

 

On my 383 the programmed idle is 950rpm but it usually bounces around 1100-1200 on the stock tach since it reads about 200rpm high. Are you still getting the MAP code after adjusting the valves? Did you prop the throttle blades open at all? You might be maxing out the IAC's capabilities. I know that I had to prop the blades open on mine when I had the 52mm ported stock t/b. The only real good way to set that is to use datamaster or other scanner to set the closed loop warm idle IAC counts to 40ish and then adjust your TPS back to about .5v

 

ive tried to run this combo with the stock tune and the madz28 tune and they both idle the same. i know the stock tune is somewhere around 650? so i should be reading around 850? right?

i only propped the tb blades open for the engine to stay running while i adjusted my valves.

what do you mean maxing out the iac?

i set my iac by depressing the gas pedal, starting engine, shutdown engine.

i never checked to see if i was throwing the map code after i adjusted my valves.

 

"I know a guy" that left off the stupid vac line going between the side of the intake manifold and the brake booster thing deal there...what a difference having that hooked up makes.

 

all vac lines are connected.

 

Try clearing the codes by pulling the PCM fuse or unhooking the battery. You will want datamaster or similar to get the car running right, it has been a priceless tool in getting everything sorted out on my car. I personally would not try running the stock tune on that engine, and my tune from Ion was incredibly accurate. We were only able to pull another 7hp out of it with a dyno tune.

By propping the t/b blades open I mean adjusting the idle screw. You need to set your IAC value by watching the IAC 'counts' on a scanner. With the stock throttle body not propped open at all you might be pegging the IAC at 160 counts just to stay alive. This will not help idle vacuum at all either.

 

Have you readjusted the valves yet?

That camshaft isn't that bad to tune in on a 383.

 

i tried the stock chip on my car just to check out the idle differences between the two.the 230/236 isnt a big cam for a 383 so i wouldnt imagine the tune is the prob especially considering the stock tune ran similarily.

i have readjusted the valves and was able to keep it running but the idle is still around 1300 on the stock tach.

ill re-check the codes as soon as im around my car again.

so noone thinks it could just be a faulty map sensor?

 

Do you have access to a laptop/datalogging cable?

 

unfortnately no.